Purification and characterization of a phagocytosis inducing factor: role in cell-substratum adherence.
The presence of two different signaling molecules is essential to induce opsonin-independent phagocytosis of particulate activators of the human alternative complement pathway by human monocytes. In addition to the involvement of a low M(r) peptide cytokine or phagocytosis inducing factor (PIF), we have now established that the participation of bacterial lipopolysaccharide is also required. PIF has been demonstrated to be present in human cell lines of different origins, e.g., WISH cells, Raji cells, U937 cells, HL-60 cells and M21 cells. PIF has been purified to apparent homogeneity from the U937 cell line by anion-exchange chromatography on DEAE-Sephacel followed by gel filtration chromatography on Sephadex G-50. On the basis of Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the apparent molecular mass has been estimated to be approximately 1,600 Da. PIF also plays an important role in the regulation of cell-substratum adherence.
Chakravarti
B
B
Department of Immunology, Scripps Research Institute, La Jolla, California, USA.
Chakravarti
D N
DN
Müller-Eberhard
H J
HJ
D002448:Cell Adhesion / Q000187:drug effects*; D002455:Cell Division; D002460:Cell Line; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D008970:Molecular Weight; D009000:Monocytes / Q000187:drug effects; D010455:Peptides / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology*
D008070:Lipopolysaccharides; D010455:Peptides